Yep Mothersmilk, every check up I had my babe was facing posterior and I was stressed out at the thought of back labour pains. I figure it was probably all the driving I did (terrible position for baby) and sitting on my bum on the couch.
Anyhoo I was too lazy to get into any real routine with exercise (my midwife recommends on hands and knees, scrubbing the floor, yeah right!) but right at the start of labour bub turned anterior and I felt no back pain at all. Straightforward easy labour & birth.
So I guess while lacking in practical help, my point is babe may well turn with no specific action, otherwise keep yourself sitting forward with a pillow behind your lower back and visualize an anterior labour might help.